During the second half of the 19th century, the citadel of Sisteron lost its fortification value with the appearance of rifled artillery that allowed very long-range firing. In 1894, the stronghold was militarily decommissioned. It served as a detention center for German prisoners during the First World War and as a guarded residence center for political prisoners and later convicts during the Second World War. Restored since 1956, it is now open to visitors who can roam the site and discover its museum and exhibitions. The citadel also hosts shows during its dance, music, and theater festival and is the subject of a nocturnal light enhancement honored with several awards.